<template>
  <div class="upload-file">
    <el-upload
      v-if="!disabled"
      multiple
      :action="uploadFileUrl"
      :before-upload="handleBeforeUpload"
      :file-list="fileList"
      :limit="limit"
      :use-original-name="useOriginalName"
      :on-error="handleUploadError"
      :on-exceed="handleExceed"
      :on-success="handleUploadSuccess"
      :show-file-list="false"
      :headers="headers"
      :data="{ path: 'file' }"
      class="upload-file-uploader"
      ref="upload"
    >
      <!-- 上传按钮 -->
      <el-button size="mini" type="primary">选取文件</el-button>
      <!-- 上传提示 -->
      <div class="el-upload__tip" slot="tip" v-if="showTip">
        请上传
        <template v-if="fileSize">
          大小不超过 <b style="color: #f56c6c">{{ fileSize }}MB</b></template
        >
        <template v-if="fileType">
          格式为 <b style="color: #f56c6c">{{ fileType.join('/') }}</b></template
        >
        的文件
      </div>
    </el-upload>

    <!-- 文件列表 -->
    <transition-group class="upload-file-list el-upload-list el-upload-list--text" name="el-fade-in-linear" tag="ul">
      <li :key="file.url" class="el-upload-list__item ele-upload-list__item-content" v-for="(file, index) in fileList">
        <el-link :href="`${file.url}`" :underline="false" target="_blank">
          <span class="el-icon-document"> {{ getFileName(file.name) }} </span>
        </el-link>
        <div class="ele-upload-list__item-content-action">
          <el-link :underline="false" @click="handleDownload(index)">下载</el-link>
          <el-link :underline="false" @click="handleDelete(index)" type="danger" v-if="!disabled">删除</el-link>
        </div>
      </li>
    </transition-group>
  </div>
</template>

<script>
import { getToken } from '@/utils/auth'

export default {
  name: 'FileUpload',
  props: {
    // 值
    value: [String, Object, Array],
    // 值类型 string字符串 object对象字符串
    valueType: {
      type: String,
      default: 'string',
    },
    // 数量限制
    limit: {
      type: Number,
      default: 5,
    },
    // 大小限制(MB)
    fileSize: {
      type: Number,
      default: 5,
    },
    // 文件类型, 例如['png', 'jpg', 'jpeg']
    fileType: {
      type: Array,
      default: () => ['doc', 'xls', 'ppt', 'txt', 'pdf'],
    },
    // 是否显示提示
    isShowTip: {
      type: Boolean,
      default: true,
    },
    //是否只读
    disabled: {
      type: Boolean,
      default: false,
    },
    // 是否使用原名
    useOriginalName: {
      type: Boolean,
      default: false,
    }
  },
  data() {
    return {
      number: 0,
      uploadList: [],
      previewImgUrl: this.$imagePreviewUrl,
      downloadImgUrl: this.$imagePreviewUrl,
      uploadFileUrl:
        process.env.VUE_APP_HOST_API == ''
          ? process.env.VUE_APP_BASE_API + '/common/upload'
          : process.env.VUE_APP_HOST_API + '/common/upload', // 上传的图片服务器地址
      headers: {
        Authorization: 'Bearer ' + getToken(),
      },
      fileList: [],
    }
  },
  watch: {
    value: {
      handler(val) {
        if (val) {
          let temp = 1
          // 首先将值转为数组
          try {
            val = JSON.parse(val)
          } catch (e) {}
          const list = Array.isArray(val) ? JSON.parse(JSON.stringify(val)) : this.value.split(',')
          // 然后将数组转为对象数组
          this.fileList = list.map((item) => {
            if (typeof item === 'string') {
              if (item.url.indexOf('http://') === -1&&item.url.indexOf('https://') === -1) {
                if (item.indexOf(process.env.VUE_APP_MEDIA_PREVIEW) === -1) {
                  item = { name: this.previewImgUrl + item, url: this.previewImgUrl + item }
                } else {
                  item = { name: process.env.VUE_APP_HOST_API + item, url: process.env.VUE_APP_HOST_API + item }
                }
              } else {
                item = { name: item, url: item, filename: item }
              }
            } else {
              if (item.url.indexOf('http://') === -1&&item.url.indexOf('https://') === -1) {
                item.url = this.previewImgUrl + item.url
              }
            }
            item.uid = item.uid || new Date().getTime() + temp++
            return item
          })
        } else {
          this.fileList = []
          return []
        }
      },
      deep: true,
      immediate: true,
    },
  },
  computed: {
    // 是否显示提示
    showTip() {
      return this.isShowTip && (this.fileType || this.fileSize)
    },
  },
  methods: {
    // 上传前校检格式和大小
    handleBeforeUpload(file) {
      // 校检文件类型
      if (this.fileType) {
        let fileExtension = ''
        if (file.name.lastIndexOf('.') > -1) {
          fileExtension = file.name.slice(file.name.lastIndexOf('.') + 1)
        }
        const isTypeOk = this.fileType.some((type) => {
          if (file.type.indexOf(type) > -1) return true
          if (fileExtension && fileExtension.indexOf(type) > -1) return true
          return false
        })
        if (!isTypeOk) {
          this.$modal.msgError(`文件格式不正确, 请上传${this.fileType.join('/')}格式文件!`)
          return false
        }
      }
      // 校检文件大小
      if (this.fileSize) {
        const isLt = file.size / 1024 / 1024 < this.fileSize
        if (file.size == 0) {
          this.$modal.msgError(`上传文件大小必须大于0字节`)
          return false
        }
        if (!isLt) {
          this.$modal.msgError(`上传文件大小不能超过 ${this.fileSize} MB!`)
          return false
        }
      }
      this.$modal.loading('正在上传文件，请稍候...')
      this.number++
      return true
    },
    // 文件个数超出
    handleExceed() {
      this.$modal.msgError(`上传文件数量不能超过 ${this.limit} 个!`)
    },
    // 上传失败
    handleUploadError(err) {
      this.$modal.msgError('上传图片失败，请重试')
      this.$modal.closeLoading()
    },
    // 上传成功回调
    handleUploadSuccess(res, file) {
      if (this.useOriginalName) {
        res.data.fileName = file.name
      }
      this.uploadList.push({ name: res.data.fileName, url: res.data.url })
      if (this.uploadList.length === this.number) {
        this.fileList = this.fileList.concat(this.uploadList)
        this.uploadList = []
        this.number = 0
        this.$emit('input', this.listToString(this.fileList))
        this.$modal.closeLoading()
      }
    },
    // 下载文件
    handleDownload(index) {
      window.open(
        this.downloadImgUrl +
          this.fileList[index].url.replace(this.previewImgUrl, '') +
          '?filename=' +
          encodeURIComponent(encodeURIComponent(this.getFileName(this.fileList[index].name)))
      )
    },
    // 删除文件
    handleDelete(index) {
      this.fileList.splice(index, 1)
      this.$emit('input', this.listToString(this.fileList))
    },
    // 获取文件名称
    getFileName(name) {
      if (name.lastIndexOf('/') > -1) {
        name = name.slice(name.lastIndexOf('/') + 1)
      }
      if (name.lastIndexOf('?') > -1) {
        name = name.slice(0, name.lastIndexOf('?'))
      }
      return name
    },
    // 对象转成指定字符串分隔
    listToString(list, separator) {
      let strs = ''
      separator = separator || ','
      if (this.valueType == 'object') {
        let arr = []
        for (let i in list) {
          if (list[i] && list[i].url) {
            arr.push({
              name: list[i].name,
              filename: list[i].filename,
              url: list[i].url.replace(this.previewImgUrl, ''),
            })
          }
        }
        strs = JSON.stringify(arr)
      } else {
        for (let i in list) {
          strs += list[i].url.replace(this.previewImgUrl, '') + separator
        }
        strs = strs != '' ? strs.substr(0, strs.length - 1) : ''
      }
      return strs
    },
  },
}
</script>

<style scoped lang="scss">
.upload-file-uploader {
  margin-bottom: 5px;
}

.upload-file-list .el-upload-list__item {
  border: 1px solid #e4e7ed;
  line-height: 2;
  margin-bottom: 10px;
  position: relative;
}

.upload-file-list .ele-upload-list__item-content {
  display: flex;
  justify-content: space-between;
  align-items: center;
  color: inherit;
}

.ele-upload-list__item-content-action .el-link {
  margin-right: 10px;
}
</style>
